Blind fasteners can be used to connect two or more components together when access is limited to one side of the components. Blind fasteners are also used with robotic assembly equipment to eliminate the need to coordinate activity on both sides of a fastener. By way of example, blind fasteners are used to attach panels to other components to make wings, flaps, ailerons and other airframe structures. Fasteners used on aerodynamically critical surfaces generally have flush heads that seat into machined or dimpled countersinks in the outer panel. Fasteners used in interior assemblies may have generally protruding heads.
Specifically regarding aircraft construction, modern aircraft are generally constructed of aluminum and laminated composite panels and structural shapes. Laminated composites, while possessing superior stiffness and strength, are prone to crushing damage unless forces are spread over enough area to minimize localized compressive stresses. In this regard, it is also important for localized compressive forces to be spread substantially uniformly over the affected area to minimize local compressive damage. Thus, in applications involving laminated composites, the size and configuration of the blind side head are important performance parameters. Fasteners with inadequate blind side heads may require thicker (and heavier) composite panels than an equivalently sized fastener with an adequately sized and configured blind side head.